feat(terminal): implement synchronized binary input handling for XTerminal

- Added `sendSessionBinaryInputWithSync` function to broadcast binary input to sync peers.
- Updated `XTerminal` component to utilize the new function for handling binary input with peer synchronization.
- Enhanced tests to verify the correct broadcasting of binary input to multiple peers without text bookkeeping.
- Introduced `escape_telnet_application_data` function to handle IAC byte escaping for telnet transport.
- Added tests for the new escaping functionality to ensure proper data handling in telnet sessions.

src-tauri/src/core/terminal_session/telnet/negotiation.rs

@@ -58,6 +58,21 @@ fn unescape_iac_iac(data: &[u8]) -> Vec<u8> {
     visible
 }
 
+fn escape_telnet_application_data(data: &[u8], raw_tcp_cli: bool) -> Vec<u8> {
+    if raw_tcp_cli {
+        return data.to_vec();
+    }
+
+    let mut escaped = Vec::with_capacity(data.len());
+    for &byte in data {
+        escaped.push(byte);
+        if byte == IAC {
+            escaped.push(IAC);
+        }
+    }
+    escaped
+}
+
 /// Strip IAC sequences from raw data, returning only user-visible bytes.
 /// Calls `on_negotiate` for each IAC command/option pair encountered.
 fn strip_telnet_commands(data: &[u8], on_negotiate: &mut impl FnMut(u8, u8)) -> Vec<u8> {

src-tauri/src/core/terminal_session/telnet/session.rs

@@ -400,6 +400,7 @@ async fn telnet_session_task(
                         let mut write_failed = None;
                         if raw {
                             let send_data = prepare_terminal_write_input(data, &encoding, true, false);
+                            let send_data = escape_telnet_application_data(&send_data, config.raw_tcp_cli);
                             if let Err(e) = writer.write_all(&send_data).await {
                                 write_failed = Some(e);
                             }

src-tauri/src/core/terminal_session/telnet/tests.rs

@@ -4,7 +4,7 @@ mod tests {
         DO, IAC, OPT_NAWS, OPT_SUPPRESS_GO_AHEAD, TelnetEnterMode, TelnetLineEditor,
         TelnetAutoLogin, TelnetAutoLoginAction, TelnetAutoLoginConfig,
         TelnetAutoLoginCredentials, TelnetSessionConfig, WILL, maybe_build_naws,
-        await_telnet_connection, negotiate_response, normalize_enter_bytes, split_write_chunks,
+        await_telnet_connection, escape_telnet_application_data, negotiate_response, normalize_enter_bytes, split_write_chunks,
         strip_telnet_commands,
     };
     use crate::error::AppError;
@@ -84,6 +84,19 @@ mod tests {
         assert!(responses.is_empty());
     }
 
+    #[test]
+    fn binary_input_escapes_iac_only_for_telnet_transport() {
+        let mouse_report = b"\x1b[M \xff\x80";
+        assert_eq!(
+            escape_telnet_application_data(mouse_report, false),
+            b"\x1b[M \xff\xff\x80"
+        );
+        assert_eq!(
+            escape_telnet_application_data(mouse_report, true),
+            mouse_report
+        );
+    }
+
     #[test]
     fn send_naws_false_prevents_naws_resize_payload() {
         let config = TelnetSessionConfig {

src/components/terminal/XTerminal.tsx

@@ -52,6 +52,7 @@ import {
   type SendSessionInputOptions,
   type SessionInputPreview,
   sendSessionBinaryInput,
+  sendSessionBinaryInputWithSync,
   sendSessionInput,
   sendSessionInputWithSync,
 } from "@/lib/sessionInput";
@@ -2362,7 +2363,12 @@ export default function XTerminal({
         requestWake("input");
       }
       if (disconnectedRef.current) return;
-      void sendSessionBinaryInput(sessionIdRef.current, data).catch(() => {});
+      const peers = syncPeerSessionIdsRef.current;
+      void (
+        peers?.length
+          ? sendSessionBinaryInputWithSync(sessionIdRef.current, data, peers)
+          : sendSessionBinaryInput(sessionIdRef.current, data)
+      ).catch(() => {});
     });
 
     const resizeDisposable = terminal.onResize(({ cols, rows }) => {

src/lib/sessionInput.test.ts

@@ -5,7 +5,12 @@ const mocks = vi.hoisted(() => ({
 }));
 vi.mock("./invoke", () => ({ invoke: mocks.invoke }));
 
-import { sendSessionBinaryInput, sendSessionInput, sendSessionInputWithSync } from "./sessionInput";
+import {
+  sendSessionBinaryInput,
+  sendSessionBinaryInputWithSync,
+  sendSessionInput,
+  sendSessionInputWithSync,
+} from "./sessionInput";
 
 describe("sendSessionInputWithSync command confirmation", () => {
   beforeEach(() => {
@@ -37,6 +42,21 @@ describe("sendSessionInputWithSync command confirmation", () => {
     });
   });
 
+  it("broadcasts binary input to sync peers without text bookkeeping", async () => {
+    await sendSessionBinaryInputWithSync("primary", "\x1b[M \xff", [
+      "peer-a",
+      "peer-b",
+    ]);
+
+    expect(mocks.invoke).toHaveBeenCalledTimes(3);
+    for (const sessionId of ["primary", "peer-a", "peer-b"]) {
+      expect(mocks.invoke).toHaveBeenCalledWith("write_bytes_to_session", {
+        sessionId,
+        data: [0x1b, 0x5b, 0x4d, 0x20, 0xff],
+      });
+    }
+  });
+
   it("registers each peer candidate before synchronized command input", async () => {
     await sendSessionInputWithSync(
       "primary",

src/lib/sessionInput.ts

@@ -182,6 +182,17 @@ export async function sendSessionBinaryInput(sessionId: string, data: string): P
   });
 }
 
+export async function sendSessionBinaryInputWithSync(
+  sessionId: string,
+  data: string,
+  peerSessionIds: string[],
+): Promise<void> {
+  await sendSessionBinaryInput(sessionId, data);
+  await Promise.allSettled(
+    peerSessionIds.map((sid) => sendSessionBinaryInput(sid, data)),
+  );
+}
+
 /**
  * Send input to a session and broadcast to all sync-group peers.
  * Peers do not emit frontend preview/history UI, but an executable command